Biomedical Engineering and Bioengineering Commons^™

Blood Flow Through The Aorta In A Mouse Model Of Atherosclerosis, J. Hough, P. Assemat, K.K.W. Siu, J.A. Armitage, K. Contreras, A. Aprico, A. Dart, J. Ching-Dusting, K. Hourigan

Computational Fluid Dynamics (CFD) in Medicine And Biology in Conjunction With the Seventh International Biofluid Mechanics Symposium

No abstract provided.

Image-Based Vs. Patient-Specific What Is The Difference, And Does It Matter?, David Steinman

Computational Fluid Dynamics (CFD) in Medicine And Biology in Conjunction With the Seventh International Biofluid Mechanics Symposium

No abstract provided.

Frequency And Distribution Of Microcalcifications In Vulnerable Plaque And Their Role In Fibrous Cap Rupture, Natalia Maldonado, Adreanne Kelly, Yuliya Vengrenyuk, Luis Cardoso, Sheldon Weinbaum

Computational Fluid Dynamics (CFD) in Medicine And Biology in Conjunction With the Seventh International Biofluid Mechanics Symposium

No abstract provided.

Evaluation Of Transfer Technologies To Preserve Shoulder Function In Sci, Karen Michelle Mann

USF Tampa Graduate Theses and Dissertations

This study investigated a series of independent unassisted and device-assisted transfers from a wheelchair to vehicle mock-up and vice versa while simultaneously capturing kinematic, kinetic and electromyographic (EMG) data of impaired volunteers. The study provides a venue for observation and evaluation of upper extremity (UE) joint stresses, muscular force and functional demands associated with transfers in persons with spinal cord injury (SCI) to ultimately prevent UE injury, minimize excessive stress, preserve functionality and limit pain. If people with SCI lose function of their UEs, due to pain and/or degeneration, they must then rely on others for everyday tasks.

Five paraplegic …

Chemical Modification Of Polysaccharides Using Reactive Extrusion, Pratik Bhandari

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The objective of this dissertation was to study the use of reactive extrusion for the chemical modifications of starch and cellulose. A carboxymethyl derivative of starch and carboxymethyl and acetate derivatives of cellulose were prepared using reactive extrusion.

Carboxymethyl starch with rapid swelling properties in water was prepared using reactive extrusion. This was achieved by controlling the gelatinization and through the use of NaOH by controlling the water/ethanol ratio. The effects of NaOH, H₂O, temperature, ethanol, sodium mono chloro acetate, sodium tripolyphosphate, citric acid, epichlorohydrin and extruder screw configuration on the degree of substitution of carboxymethyl starch were …

Methods For Enhancing Expression Of Secondary Cell Wall Cellulose Synthases In Plants, Chandrashekhar P. Joshi

Michigan Tech Patents

Described are methods for making transgenic plants capable of expressing secondary cell wall cellulose synthases and methods of enhancing expression of secondary cell wall cellulose synthases in plants. Also described are plants produced by the methods. Plants comprising at least three exogenous polynucleotides encoding secondary cell wall cellulose synthases are also provided.

The Latest Lessons Learned From Retrieval Analyses Of Ultra-High Molecular Weight Polyethylene, Metal-On-Metal, And Alternative Bearing Total Disc Replacements, Steven M. Kurtz, Jeffrey M. Toth, Ryan Siskey, Lauren Ciccarelli, Daniel Macdonald, Jorge Isaza, Todd Lanman, Ilona Punt, Marla Marla Steinbeck, Jan Goffin, André Van Ooij

Biomedical Engineering Faculty Research and Publications

Knowledge regarding the in vivo performance and periprosthetic tissue response of cervical and lumbar total disc replacements (TDRs) continues to expand. This review addresses the following 4 main questions: (1) What are the latest lessons learned from using polyethylene in large joints and how are they relevant to current TDRs? (2) What are the latest lessons learned regarding adverse local tissue reactions from metal-on-metal cobalt-chrome bearings in large joints and how are they relevant to current TDRs? (3) What advancements have been made in understanding the in vivo performance of alternative biomaterials, such as stainless steel and polycarbonate urethane, for …

Development Of A Standardized Method For Comparing Biomechanical Properties Of Various Sternal Closure Techniques, Ramzi P. Hawit

Master's Theses

Background:

33.6% of all deaths in America are caused by cardiovascular disease. An estimated 82.6 million adults (>1 in 3) in America have some form of cardiovascular disease. There were over 400,000 bypass surgeries requiring open-heart surgery. Sternal dehiscence is associated with a morbidity rate of over 47% if mediastinitis supervenes. A rigid closure is required to avoid healing complications, and wire, plates, and bands are all used in an attempt to make a better closure. The purpose of this study it to compare multiple closures and validate a new testing method.

Methods:

Polyurethane foam blocks will be used, …

Novel On-Demand Droplet Generation For Selective Fluid Sample Extraction, Melinda Simon, Jeffrey Fisher, Melinda Simon, Abraham Lee

Faculty Publications

 A novel microfluidic device enabling selective generation of droplets and encapsulation of targets is presented. Unlike conventional methods, the presented mechanism generates droplets with unique selectivity by utilizing a K-junction design. The K-junction is a modified version of the classic T-junction with an added leg that serves as the exit channel for waste. The dispersed phase fluid enters from one diagonal of the K and exits the other diagonal while the continuous phase travels in the straight leg of the K. The intersection forms an interface that allows the dispersed phase to be controllably injected through actuation of an elastomer …

Relationship Between The Foveal Avascular Zone And Foveal Pit Morphology, Adam M. Dubis, Benjamin R. Hansen, Robert F. Cooper, Joseph Beringer, Alfredo Dubra, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

Purpose. To assess the relationship between foveal pit morphology and size of the foveal avascular zone (FAZ).

Methods. Forty-two subjects were recruited. Volumetric images of the macula were obtained using spectral domain optical coherence tomography. Images of the FAZ were obtained using either a modified fundus camera or an adaptive optics scanning light ophthalmoscope. Foveal pit metrics (depth, diameter, slope, volume, and area) were automatically extracted from retinal thickness data, whereas the FAZ was manually segmented by two observers to extract estimates of FAZ diameter and area.

Results. Consistent with previous reports, the authors observed significant variation in foveal pit …

Persistent Vascular Collagen Accumulation Alters Hemodynamic Recovery From Chronic Hypoxia, Diana M. Tabima, Alejandro Roldan-Alzate, Zhijie Wang, Timothy A. Hacker, Robert C. Molthen, Naomi C. Chesler

Biomedical Engineering Faculty Research and Publications

Pulmonary arterial hypertension (PAH) is caused by narrowing and stiffening of the pulmonary arteries that increase pulmonary vascular impedance (PVZ). In particular, small arteries narrow and large arteries stiffen. Large pulmonary artery (PA) stiffness is the best current predictor of mortality from PAH. We have previously shown that collagen accumulation leads to extralobar PA stiffening at high strain (Ooi et al. 2010). We hypothesized that collagen accumulation would increase PVZ, including total pulmonary vascular resistance (Z₀), characteristic impedance (Z_C), pulse wave velocity (PWV) and index of global wave reflections (P_b/P …

Dc Dielectrophoretic Assisted Anti-Fouling Filtration System, Nathan M. Cohen

Master's Theses

Filtration processes, whether on the microfluidic, clinical treatment systems, or industrial scale (e.g., point-of-care diagnostics, dialysis, and biopharmaceutical manufacturing, respectively), are often inseparable from membrane clogging (fouling). As a consequence, most, if not all, filtration systems require frequent maintenance to maintain functionality and efficiency. The thesis of this project hypothesizes that Dielectrophoresis can be combined with standard filtration to reduce filter fouling, extending membrane life, and enabling continuous operation. This project investigates a method to reduce fouling, add specificity and efficiency, and decrease the cost and challenge of filtration based biofluid separations.

To substantiate this thesis, we designed, fabricated, and …

Adding Ros Scavengers To Cold K+ Cardioplegia Reduces Superoxide Emission During 2 H Global Cold Cardiac Ischemia, Mohammed Aldakkak, David F. Stowe, James S. Heisner, Matthias L. Riess, Amadou K.S. Camara

Biomedical Engineering Faculty Research and Publications

We reported that the combination of reactive oxygen species (ROS) quenchers Mn(III) tetrakis (4-benzoic acid) porphyrin (MnTBAP), catalase, and glutathione (MCG) given before 2 hours cold ischemia better protected cardiac mitochondria against cold ischemia and warm reperfusion (IR)-induced damage than MnTBAP alone. Here, we hypothesize that high K⁺ cardioplegia (CP) plus MCG would provide added protection of mitochondrial bioenergetics and cardiac function against IR injury. Using fluorescence spectrophotometry, we monitored redox balance, ie reduced nicotinamide adenine dinucleotide and flavin adenine dinucleotide (NADH/FAD), superoxide (O₂ ^•−), and mitochondrial Ca²⁺ (m[Ca²⁺]) in the left ventricular free …

Subclinical Photoreceptor Disruption In Response To Severe Head Trauma, Kimberly E. Stepien, Wanda M. Martinez, Adam M. Dubis, Robert F. Cooper, Alfredo Dubra, Joseph Carroll

Biomedical Engineering Faculty Research and Publications

Commotio retinae is a transient opacification of the retina due to outer retinal disruption occurring in a contrecoup fashion after blunt trauma.Histological studies in animals and humans after ocular blunt trauma have revealed that disruption occurs at the level of the photoreceptor outer segments and retinal pigment epithelium.Recent reports using optical coherence tomography (OCT) have shown detectable disruption at the level of the photoreceptor inner segment/outer segment junction and retinal pigment epithelium and that these changes may be reversible over time with restoration of normal outer retinal architecture.However, the resolution of existing OCT technology may not be sensitive enough to …

Damage To Mitochondrial Complex I During Cardiac Ischemia Reperfusion Injury Is Reduced Indirectly By Anti-Anginal Drug Ranolazine, Ashish K. Gadicherla, David F. Stowe, William E. Antholine, Meiying Yang, Amadou K.S. Camara

Biomedical Engineering Faculty Research and Publications

Ranolazine, an anti-anginal drug, is a late Na⁺ channel current blocker that is also believed to attenuate fatty acid oxidation and mitochondrial respiratory complex I activity, especially during ischemia. In this study, we investigated if ranolazine's protective effect against cardiac ischemia/reperfusion (IR) injury is mediated at the mitochondrial level and specifically if respiratory complex I (NADH Ubiquinone oxidoreductase) function is protected. We treated isolated and perfused guinea pig hearts with ranolazine just before 30 min ischemia and then isolated cardiac mitochondria at the end of 30 min ischemia and/or 30 min ischemia followed by 10 min reperfusion. We utilized …

Enhanced Charge-Independent Mitochondrial Free Ca2+ And Attenuated Adp-Induced Nadh Oxidation By Isoflurane: Implications For Cardioprotection, Bhawana Agarwal, Amadou K.S. Camara, David F. Stowe, Zeljko J. Bosnjak, Ranjan K. Dash

Biomedical Engineering Faculty Research and Publications

Modulation of mitochondrial free Ca^{2 +} ([Ca^{2 +}]_m) is implicated as one of the possible upstream factors that initiates anesthetic-mediated cardioprotection against ischemia–reperfusion (IR) injury. To unravel possible mechanisms by which volatile anesthetics modulate [Ca^{2 +}]_m and mitochondrial bioenergetics, with implications for cardioprotection, experiments were conducted to spectrofluorometrically measure concentration-dependent effects of isoflurane (0.5, 1, 1.5, 2 mM) on the magnitudes and time-courses of [Ca^{2 +}]_m and mitochondrial redox state (NADH), membrane potential (ΔΨ_m), respiration, and matrix volume. Isolated mitochondria from rat hearts were energized with 10 …

A Multifaceted Analysis Of Early Stage Non-Small Cell Lung Cancer Data, Madhusmita Behera

USF Tampa Graduate Theses and Dissertations

Some early stage NSCLC patients have a better survival prospects than others. In any event, the long-term prognosis for NSCLC patients is poor. Various measures were investigated to gain a better understanding of those patient characteristics that confer better survival or predict disease recurrence. A dataset comprised of stage 1 NSCLC patients (n=162) that underwent resection was investigated. Clinical variables (CVs) and tissue microarray (TMA) images with DNA repair protein and standard H&E expressions were investigated. Patients were dichotomized into two groups by survival characteristics and logistic regression (LR) modeling was used to predict favorable survival outcome. Various patient strata …

New Window On Optical Brain Imaging; Medical Development, Simulations And Applications, Chemseddine Mansouri, Nasser H. Kashou

Biomedical, Industrial & Human Factors Engineering Faculty Publications

In this chapter we hope to give a technological review of near-infrared light and systems, discuss optode design considerations including background on the fiber design as it relates to this field and finally touch on current trends and applications. For the latter, we will focus on diffusion theory and simulation of photon propagation using a head model. We will follow this with concluding remarks.

Sendai Virus-Based Liposomes Enable Targeted Cytosolic Delivery Of Nanoparticles In Brain Tumor-Derived Cells, Veronica Dudu, Veronica Rotari, Maribel Vazquez

Publications and Research

BACKGROUND: Nanotechnology-based bioassays that detect the presence and/or absence of a combination of cell markers are increasingly used to identify stem or progenitor cells, assess cell heterogeneity, and evaluate tumor malignancy and/or chemoresistance. Delivery methods that enable nanoparticles to rapidly detect emerging, intracellular markers within cell clusters of biopsies will greatly aid in tumor characterization, analysis of functional state and development of treatment regimens.

RESULTS: Experiments utilized the Sendai virus to achieve in vitro, cytosolic delivery of Quantum dots in cells cultured from Human brain tumors. Using fluorescence microscopy and Transmission Electron Microscopy, in vitro experiments illustrated that these virus-based …

Quantitative Cherenkov Emission Spectroscopy For Tissue Oxygenation Assessment, Johan Axelsson, Adam K. Glaser, David J. Gladstone, Brian W. Pogue

Dartmouth Scholarship

Measurements of Cherenkov emission in tissue during radiation therapy are shown to enable estimation of hemoglobin oxygen saturation non-invasively, through spectral fitting of the spontaneous emissions from the treated tissue. Tissue oxygenation plays a critical role in the efficacy of radiation therapy to kill tumor tissue. Yet in-vivo measurement of this has remained elusive in routine use because of the complexity of oxygen measurement techniques. There is a spectrally broad emission of Cherenkov light that is induced during the time of irradiation, and as this travels through tissue from the point of the radiation deposition, the tissue absorption and scatter …